<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>事件代理</title>
  <style>
    .parent {
      height: 500px;
      background-color: powderblue;
      overflow: hidden;
    }
    .child {
      width: 100px;
      height: 100px;
      background-color: seagreen;
      margin: 50px;
      float: left;
    }
  </style>
  <script>
    window.onload = function() {
      
      // 1.获取dom节点
      var parent = document.getElementsByClassName('parent')[0]
      // 动态添加dom节点
      var cloneDom = parent.children[0].cloneNode(true)
      parent.appendChild(cloneDom)

      var child = document.getElementsByClassName('child')
      // 将类数组对象转成数组
      child = Array.prototype.slice.call(child)
      
      console.log(child);
      // 遍历数组
      child.forEach(function(item,index) {
        // 添加绑定事件
        item.onclick = function() {
          console.log(index);
        }
      })

      
    }
  </script>
</head>
<body>
  <div class="parent">
    <div class="child">one</div>
    <div class="child">two</div>
    <div class="child">three</div>
    <div class="child">four</div>
    <div class="child">five</div>
  </div>
</body>
</html>